<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
	b
	<script type="text/javascript">
		function goBack() {
			window.history.go(-1);
		}
		function goForward() {
			window.history.go(1);
		}
	</script>
	<a href="09c.html">c</a>
	<input type="button" value="后退" onclick="goBack()" />
	<input type="button" value="前进" onclick="goForward()" />
</body>
</html>